Method and apparatus for texturing yarn

ABSTRACT

A permanent zig-zag crimp or helical configuration is imparted to a length of yarn, thread, tow or continuous filament textile material by extruding the length of yarn from a high pressure chamber, after which the yarn impinges on obstructing means for the imparting of the crimp. The length of yarn is held in the crimped state and heated in order to form a permanent set, followed by cooling of the strip of yarn. The extrusion opening in the high pressure chamber through which the yarn is extruded is substantially equal in cross-section to the cross-section of the yarn in order to achieve extrusion of the yarn from the high pressure chamber.

United States Patent [191 [111 3,805,342 Shattuck 1 Apr. 23, 1974 METHODAND APPARATUS FOR 3,626,557 12/1971 Chudgar et a1. ..28/1.3

TEXTURING YARN Primary Examiner--Louis K. Rimrodt [5 7] ABSTRACT Apermanent zig-zag crimp or helical configuration is imparted to a lengthof yarn, thread, tow 0r continuous filament textile material byextruding the length of yarn from a high pressure chamber, after whichthe yarn impinges on obstructing means for the imparting of the crimp.The length of yarn is held in the crimped state and heated in order toform a permanent set, followed by cooling of the strip of yarn. Theextrusion opening in the high pressure chamber through which the yarn isextruded is substantially equal in crosssection to the cross-section ofthe yarn in order to achieve extrusion of the yarn from the highpressure chamber.

16 Claims, 12 Drawing Figures FEES SUE/ZED Fl U/D .45 cooulva coou/w;

HEATING- HEATING PATENTEDAPR23 1974 sum 3 BF 4 .95 QQQU mm v v l I I IMETHOD AND APPARATUS FOR TEXTURING YARN The present invention relates tothe manufacture of yarn and more particularly to a method and apparatusfor texturing yarn, or stated differently, for imparting a permanentzig-zag crimp or helical configuration in yarns, thread, tow orcontinuous filament textile materials.

In order to provide the desired bulkiness, soft texture, pleasingappearance and stretchiness to a fabric article, it has been founddesirable in the production of the fabric articles comprising yarn madeof natural or synthetic textile filaments and particularly those whichare of the heat settable variety, to impart a permanent zig-zag, crimp,helical configuration, coils and the like to the filaments at some stagein their manufacture.

In the development of various techniques for texturingyarn, it wasdetermined at an early stage that the process should be a continuousprocess, as contrasted to a batch process. The latter process involvedexpensive equipment which could handle only a limited amount of yarn,whereby the batch process was ex tremely expensive and time consuming.

Early efforts directed to a continuous process included the developmentof what is commonly known as a stuffer crimper in which a length of yarnis driven by a pair of rolls into a confined region so as to effectivelystuff the length of yarn whereby crimping of the yarn occurs. Furtherefforts to refine a continuous texturing process resulted in thedevelopment of the aspirating technique wherein a length of yarn iscontacted with a stream of fluid passing generally axially of the yarmto provide the driving force for the yarn. In a conventional aspiratingapparatus the yarn would be passed through an orifice which was largeenough to accommodate the yarn and a sufficient amount of air flow toeffectively carry the yarn, with the size of the orifice being 8-10times greater than the size of the yarn.

The present invention is directed to an entirely different concept forconveying thelength of yarn to an obstructing means whereat crimping isachieved. Fundamentally, the basic concept of the subject invention isto extrude a length of yarn through an extrusion opening provided in apressurized container, with the extrusion being accomplished by means ofthe differential pressure between the high pressure container in whichthe yarn initially passes, and the atmospheric air pressure existingexternally of the chamber when the yarn is crimped. Located in theimmediate vicinity of the extrusion opening through which the yarn isextruded is a suitable obstruction means, somewhat akin to the stuffercrimper arrangement in the prior techniques, whereby the extruded yarnis allowed to zig-zag, coil, and generally twist and fold about itselfin order to impart the desired texture to the yarn. The apparatus of thesubject invention basically comprises a high pressure chamber having anextrusion opening substantially corresponding in cross-section to thecrosssection of the yarn. The chamber is provided with a source ofpressurized fluid. When the yarn is threaded through the extrusionopening, the chamber is substantially closed, except with respect to thefact that the yarn extending through the extrusion opening effectivelydefines the weakest point in the chamber, and when the chamber is filledwith high pressure fluid, the differential pressure internally andexternally of the chamber results in the development of an axial forcein the yarn corresponding to the differential pressure internally andexternally of the chamber multiplied by the cross-section of theopening. This unbalanced force gives rise to an axial driving force inthe length of yarn, resulting in the yarn being effectively extrudedfrom the chamber, and the axial force of the extruded yarn is sufficientto provide the necessary axial force for achieving texturing of the yarnwhen the latter im pinges upon an obstruction means located immediatelydownstream of the extrusion opening.

Fundamentally, the method of the subject invention for imparting atexture to a length of yarn comprises the steps of extruding a length ofyarn from a pressurized container through an extrusion openingcorresponding in cross-section to the cross-section of the yarn, andsubsequently causing the yarn to impinge on an obstructing meansdisposed externally of the pressurized chamber in the vicinity of theopening. In order to establish a permanent set in the yarn, theadditional steps of heating of the yarn and cooling of the yarn may beemployed, or other steps depending on the composition of the yarn.

As is readily apparent, when the pressure within the chamber ismaintained at a constant level, the axial driving force or extrudingforce acting on the yarn in order to extrude same from the containerremains constant. This is particularly desirable in order to achieveuniform texturing of the yarn. In order to control the rate at which theyarn is extruded from the pressurized container, suitable metering rollsare provided within the container, and furthermore, where theobstruction means comprises a pair of drive rolls into the pins of whichthe extruded yarn impinges, suitable control means may be provided tocoordinate the operation of the metering rolls within the pressurizedcontainer and the drive rolls defining the obstruction means of theapparatus.

Of extreme importance is the relationship between the diameter of theyarn and the extrusion opening in the pressurized container. Severaltechniques may be employed in order to meet the close fit requiredbetween the size of the yarn and the size of the extrusion opening inorder to achieve the extruding force. In one embodiment, the extrusionis of a fixed diameter type, corresponding in cross-section to thecross-section of the yarn, whereas in another embodiment the extrusionopening is formed of two cooperating portions which are relativelymovable in order to facilitate the initial threading of the yarn throughthe opening. In still additional embodiments, a flexible sealing meansis employed in conjunction with the extrusion opening in order to insurea substantially air-tight relationship between the opening and the yarn,in which case a suitable seal is provided in the extrusion opening. Theseal may be formed by means of high vicosity fluid in the area of theopening, with the yarn passing through the fluid and cooperating withthe fluid in order to define a seal with the extrusion opening. In otherembodiment, the seal between the extrusion opening and the yarn isdefined by a flexible diaphragm having an opening corresponding to thecross-section of the yarn. With the latter configuration, the diaphragmwould be sufficiently flexible such that a knot in the length of yarncould readily pass through the opening without causing an interruptionin the continuous operation of the apparatus. In other embodiments, theextrusion opening in the pressurized container could be defined by aporous metal structure and additional means may be provided for pumpingoil or other viscous fluid, under high pressure, through the porousmetal so that a constant source of sealant material would be provided inthe region of the opening to maintain the required air-tight sealbetween the yarn and the opening. In still another embodiment, atransverse opening is provided through the wall of the container leadingto the extrusion opening, and pressurized oil or other sealant fluid ispumped into the region of the extrusion opening to maintain thecontinuous seal for insuring the extrusion operation of the subjecttexturing process.

Accordingly, it is an object of the subject invention to provide anewand improved method and apparatus for texturing yarn, and moreparticularly, a new and improved method and apparatus which employs theunique concept of extruding yarn in order to impart thereto thenecessary axial force for achieving crimping/texturing of the yarn.

Further objects and advantages of the invention will appear from thefollowing detailed description, taken in conjunction with the followingdrawings in which:

FIG. 1 is a schematic illustration of a first embodiment of thetexturing apparatus of the subject invention;

FIG. 2 is a sectional view taken along 2-2 in FIG. 1;

FIG. 3 is a detailed sectional view of the extrusion opening of anapparatus according to the subject invention, and including a schematicrepresentation of the pressure forces acting within the pressurizedcontainer;

FIG. 4 illustrates a second embodiment of the texturing apparatusaccording to the subject invention;

FIG. 5 illustrates a third embodiment of the texturing apparatusaccording to the subject invention;

FIG. 6 illustrates an arrangement of heating rolls for pre-heating thelength of yarn prior to the extrusion operation;

FIG. 7 illustrates a fourth embodiment of the texturing apparatus madeaccording to the subject invention; and

FIGS. 812 illustrate alternative constructions for the extrusion openingof the subject invention.

Before describing in detail the several embodiments of the subjectinvention, it should be understood that the term yarn as used herein isintended to apply not only to fiber assemblies (whether natural ormanmade) spun from staple-length fibers, but also to such assembliescomprised of continuous filaments; blends of staple-length fibers andcontinuous filaments; and to yarns consisting of a single ply or severaltwisted or untwisted plies.

Referring to FIG. 1, a first embodiment of the apparatus made accordingto the subject invention basically comprises an air-tight chamber orcontainer 10 having an inlet conduit 12 for receiving pressurized fluidsuch as air, gas, or steam. The pressurized fluid is at a pressuregreater than 100 p.s.i.g. in order to develop sufficient extrusion forcefor crimping the yarn. In addition, the chamber 10 has an extrusionopening 14. Of primary importance is the size of the extrusion opening14 relative to the length of yarn Y to be textured, and moreparticularly, the cross-section of the extrusion opening 14 must besubstantially equal in size to the cross-section of the yarn Y to betextured. The latter is fed from a pirn 16 over roller guides 18,18through a tension disc 20 and through a yarn inlet opening 22 formed inthe chamber 10. As the yarn Y passes through the interior of the chamber10 it is metered by means of metering rolls 24,24 prior to reaching theextrusion opening 14. The metering rolls also function to prevent theyarn from being driven or extruded out of the chamber 10 through theinlet opening 22.

Located immediately outside of the chamber 10 is the vicinity of theextrusion opening 14 is an obstructing means 30 wherein crimping of theyarn is achieved. In the embodiment shown in FIG. 1, the obstructionmeans is defined at the nip of a roller 32 and a continuous belt 34driven by rollers 36,36. As more distinctly illustrated in FIG. 2,roller 32 has a peripheral groove 32a therein for accomodating thelength of crimped yarn as it leaves the nip of the belt 34 and roller 32which defines the obstruction means. The crimp or textured yarn,designated by the numeral 40 is then passed over roller guide 42 to atake-up pirn 44 or collection means (now shown) for further processinginto a fabric article.

The metering rolls 24,24 within the chamber 10 are interconnected withthe obstruction means, and in particular the roll 32 by suitablecoordinating means (schematically illustrated in FIG. 1 by dotted line46) so as to insure that the metering of the yarn Y from the chamber 10is coordinated with the collection of the textured yarn, and, by thiscoordination to control the rate, type and degree of crimping thatoccurs at the obstruction means 30.

In the operation of the apparatus, the yarn is threaded from the pirn 16over the guide rollers 18 and the alignment funnel 20 through the yarnentrance opening 22 into the chamber 10, through the metering rolls24,24 and thence through the extrusion opening 14. As indicatedpreviously, the cross-section of the extrusion opening substantiallycorresponds to the corsssection of the yarn in order to insure theproper operation of the subject apparatus. In order to obtain anunderstanding of how the extrusion of the yarn is achieved by thesubject apparatus, reference is made to FIG. 3 which provides a detailedsectional view of an extrusion opening 14 provided in a pressurizedchamber 10, and having a continuous length of yarn Y extendingtherethrough. The chamber 10 is pressurized and the pressure forceswhich are uniformly distributed within the chamber 10 are indicated bythe arrows P. As is readily apparent, equal and opposite pressure forcesexist on opposite sides of the yarn, except for an unbalanced pressureforce F,, which exists across an imaginary plane, designated by theletter C, extending across the cross-section of the strip of yarn Y. Theexterior of the chamber 10 is at atmospheric pressure P, whereby anopposite axial force F exists in the yarn as a result of the atmosphericpressure acting across a similar cross-section of the yarn, designatedby C. Since the pressure force F within the chamber is greater than theatmospheric pressure force F, and since the crosssection of the yarn isidentical within and without of the chamber 10, there is an unbalancedforce (corresponding to the difference in magnitude between F and Facting on the yarn in an axial direction causing the yarn to be extrudedfrom the pressurized container toward the obstruction means.

As the yarn leaves the extrusion opening 14 of the pressurized chamber10, it impinges upon the obstruction means 30 defined at the nip of thebelt and roller, and at such point folds over upon itself and zig-zags,crimps, or folds to a helical configuration so as to result in texturingof the yarn. If desired, the roller 32 may be heated so as to form apermanent set in the yarn, with the heating means for the roller 32being schematically designated by numeral 48.

In summary, the method of the subject invention comprises the first stepof extruding a length of yarn Y from the pressurized container throughthe extrusion opening 14 whose cross-section closely approximates thecross-section of the yarn, followed by the step of causing the yarn toimpinge on the obstructing means 30 in order to texture the yarn.Additional steps of heating the yarn, as well as cooling the yarn may beadded to the process.

A second embodiment of the subject apparatus is illustrated in FIG. 4wherein like numbers designate similar structure as found in thepreferred embodiment illustrated in FIG. 1. Accordingly, the apparatusof the second embodiment includes a pressurized chamber 10 provided withan inlet 12 for pressurized fluid, a pair of metering rolls 24,24, ayarn entrance opening 22 provided in the chamber 10, and an obstructionmeans defined between the nip of a pair of rolls 50,50. The obstructionrolls 50,50 are interconnected with the metering rolls 24,24 by suitableinterconnection linkages 46 so as to coordinate the operation of theapparatus, and more particularly to coordinate the rate at which theyarn is extruded from the pressurized chamber and the rate at which thepacked mass of crimped yarn is carried along by the obstruction means.Dowstream of the obstruction rollers 50,50 there is provided a tube 52through which the yarn is guided. The first portion of the tube 52through which the textured yarn 40 is conducted is heated by heatingmeans 54,54 so as to form a set in the textured yarn 40 while theopposite end of the plates are surrounded by cooling means 56,56 inorder to permanently set the textured yarn 40.

Referring now to FIG. 5, a third embodiment of the subject apparatus ischaracterized by the pressurized chamber 10 being of sufficient size toaccommodate the pirn 16 whereby a yarn entrance opening is not required.Asin the previous embodiments the extrusion opening 14 corresponds insize to the size of the yarn and the metering rolls 24,24 areinterconnected with the rollers 60 for the belt driven obstruction means30. The latter include heating means 64,64 and cooling means 66,66 whichoperate to respectively set and per manently condition the textured yarnprior to being collected onto pirn 44.

FIG. 6 illustrates an arrangement of a pair of rollers 70,70 which maybe used in lieu of the metering rolls 24 within the pressurized chamber10. One or both of the rollers 70,70 may be heated for pre-heating ofthe yarn prior to extrusion, and the arrangement of wrapping the yarn Yseveral times around the rollers 70,70 enables metering of the yarn fromthe chamber 10.

Alternatively, the pressurized fluid input through inlet conduit 12 tothe chamber 10 may be steam or hot air in order to preheat the yarn Yprior to extrusion and crimping.

Referring now to FIG. 7, a fourth embodiment of the subject apparatus isillustrated wherein the obstruction means 30 takes the form of a rollerdriven porous belt 80, the underside of which is subject to a vacuum asdesignated at 82, whereby as the yarn Y leaves the extrusion opening 14it immediately contacts the porous belt 80, and the momentum of the yarnimpringing onto the previously packed mass causes crimping and thevacuum created below the porous belt causes the packed mass of yarn tostay on the moving belt past the source of heat, for example, aninfrared lamp 84 which heat sets the yarn to a permanent texturedcondition. Next, the yarn is pulled off the belt to be wound on a pirnor other collection means for further processing into fabric articles.

FIGS. 8 through 12 designate various alternative constructions of theextrusion opening 14 in order to ensure the sufficiently close fitbetween the size of the yarn and the size of the extrusion opening toachieve the extrusion effect previously described. It might be notedthat the extrusion effect is generally similar to that which occurs in abullet fired from a rifle. The bullet constitutes an obstruction in thebore of the rifle, and the differential pressure acting on opposite endsof the bullet results in a force which is directly proportional to thecross-section of the bullet, and this force effectively extrudes thebullet from the bore in a manner similar to the extrusion process of thesubject invention. This is to be contrasted with the prior arttechniques wherein the axial air flow of the aspirating devices iseffective in carrying along and operating along the cross-sectionalperiphery of the yarn so as to provide the axial driving force for theyarn.

As is readily apparent, one of the primary considerations in theconstruction of the extrusion opening is to insure that the yarneffectively forms a substantially airtight seal with the extrusionopening. In order to enhance the seal, one possible construction of theextrusion opening is illustrated in FIG. 8 wherein the extrusion opening14 in the pressurized container 10 is somewhat greater in size than thecross-section of the yarn Y, and in order to provide an effective seal,oil or other highly viscous fluid is provided in the vicinity of theextrusion opening 14. The oil or other highly viscous fluid 90 acts as aseal between the yarn Y and the structural wall of the opening 14, andsince the oil is flexible, in the event that the yarn has a knot or slubY, in it, the knot or slub can readily pass through the extrusionopening in a smooth, continuous flow rather than causing a temporaryinterruption in the processing of the yarn.

In FIG. 9, the extrusion opening 14 may be formed by means of a porousmetal plug having an orifice therein, which porous metal would bepermanently secured to the pressurized container 10. Along the peripheryof the plug 100 there is provided a manifold 102 which is supplied witha source of oil 104 or other fluid under high pressure. As in the: caseof FIG. 8, the extrusion opening defined in the porous metal would beslightly larger than the size of the yarn Y whereby slubs or knots Ycould readily pass therethrough. In order to form an effective seal, theoil or other fluid under high pressure would be pumped through themanifold 102 and forced through the porous metal 100-so as to constantlyprovide a fluid seal in the extrusion opening 14.

FIG. 10 provides still another construction of the extrusion opening inthat the opening would be of slightly greater size than thecross-section of the yarn, and a transverse opening 108 would beprovided in the wall of the pressurized container 10 so that oil 110 orother fluid under pressure may be constantly applied to the vicinity ofthe extrusion opening 14 to maintain an effective fluid seal therein andlubricate the opening 108.

FIG. 11 illustrates another construction of the extrusion opening inwhich the opening would be defined by a flexible diaphragm 110 having anorifice 112, corresponding generally in size to the cross-section of theyarn. In addition a body of oil or other highly viscous fluid may beprovided in the vicinity of the extrusion opening to maintain a constantair-tight seal across the extrusion opening, and the combination of theflexible diaphragm 110 and oil ensures that even if a know or slub Y,were required to be passed through the extrusion opening, nodiscontinuity in the operation of the apparatus would be required.

FIG. 12 illustrates still another form of extrusion opening 14, and onewhich is particularly advantageous during the initial setting up of thesubject apparatus. The extrusion opening is defined by two cooperatingsections 120 of the container 10, each section 120 being pivotallyattached to the pressurized contained by hinge 122. By this arrangement,with the sections 120 rotated to the inoperative positions (shown indotted lines) the yarn Y may be readily threaded into the cut-out 124 ina section 120 and then the sections are rotated ot the operativepositions (shown in solid lines) thereby completing the threadingoperation.

As previously noted, for some yarn materials, preheating of the yarnprior to crimping may be desirable. In such cases, preheating may beeffected either before the yarn enters the chamer or while the yarn isin the chamber. As is readily apparent, the invention thus conceived issuspectible to various modifications, alternations and changes, all ofwhich are to be considered as included within the scope of the inventionas defined by the appended claims.

What is claimed is:

1. Apparatus for imparting a texture to yarn comprising a chamber havingan opening substantially corresponding in cross-section to thecross-section of said yarn, a source of pressurized fluid incommunication with said chamber, and obstruction means disposed adjacentsaid opening externally of the chamber in ambient air whereby when saidyarn is threaded through said opening and pressurized fluid is providedin said chamher, the yarn is extruded from the chamber and impinges onsaid obstructing means resulting in texturing of the yarn.

2. Apparatus for imparting a texture to yarn as in claim 1 furtherincluding means for heating said textured yarn, and means for coolingsaid textured yarn.

3. Apparatus for imparting a texture to a length of yarn as in claim 1wherein the pressurized fluid is steam.

4. Apparatus for imparting a texture to yarn as in claim 1 furtherincluding metering rolls disposed in said chamber, said yarn beingpassed through the nip of said metering rolls prior to being threadedthrough said opening.

5. Apparatus for imparting a texture to yarn as in claim 1 wherein thefluid pressure within the chamber is greater than 100 p.s.i.g.

6. Apparatus for imparting a texture to yarn as in claim 1 furtherincluding a pair of metering rolls disposed in said chamber for meteringthe yarn prior to its extrusion from the chamber, and further includinga pair of crimping rolls disposed externally of the chamber, the nips ofsaid crimping rolls defining the obstruction means, and means forcoordinating the rotating of said metering rolls and said crimpingrolls.

7. Apparatus for imparting a texture to yarn as in claim 1 wherein saidchamber is provided with a second opening, said second openingsubstantially corresponding in cross-section to the cross-section ofsaid yarn, which yarn is, in turn, threaded through said second opening,through said pressurized chamber, and through said first extrusionopening.

8. Apparatus for imparting a texture to yarn as in claim 1 wherein saidpressurized fluid is air.

9. Apparatus for imparting a texture to yarn as in claim 1 wherein saidobstruction means comprises of a pair of spaced, roller mounted belts,and further including heating means and cooling means disposed in thevicinity of said belts in order to successively heat and cool thetextured yarn passing therethrough.

10. Apparatus for imparting a texture to yarn as in claim 1 wherein saidchamber includes two relatively moveable portions thereof defining theopening corresponding in cross-section to the cross-section of saidyarn.

11. Apparatus for imparting a texture to yarn as in claim 1 wherein theobstruction comprises a roller driven porous belt, the outside surfaceof said belt receiving the yarn extruded from said opening, while theinside surface of said belt is in communication with a source of reducedpressure, and further including heating means for heating said crimpedyarn to permanently set same.

12. Apparatus for imparting a texture to yarn as in claim 1 wherein ahigh viscous fluid is provided in the region of said extrusion openingto define an air-tight seal therewith through which said yarn isextruded.

13. Apparatus for imparting a texture to yarn as in claim 1 wherein saidopening is defined by a porous metal plug fixedly secured in the wall ofsaid chamber, which plug includes an opening through which the yarn isthreaded, said plug further including a peripherial manifold which is incommunication with a source of high pressure fluid, which fluid passesthrough the porous metal plug to the vicinity of said opening in theplug for forming an air-tight seal through which the yarn is extruded.

14. Apparatus for imparting a texture to yarn as in claim 1 wherein saidpressurized chamber includes a transverse opening extending transverseto the longitudinal axis of said opening, and a source of pressurizedfluid in communication with said transverse opening so as to provide acontinuous source of pressurized high viscous fluid to the opening forforming an air-tight seal through which said yarn is passed.

15. A method of imparting a texture to yarn comprising the steps of:

extruding said yarn from a pressurized contain to ambient air through anopening therein corresponding in cross-section to the crosssection ofsaid yarn; and

causing said yarn to impinge on an obstructing means in ambient airdisposed externally of said pressuirzed chamber in the vicinity of saidopening.

16. A method for imparting a texture to a length of yarn as in claim 15further including the steps of:

heating said yarn to form a permanent set in the yarn;

and

cooling said yarn.

1. Apparatus for imparting a texture to yarn comprising a chamber havingan opening substantially corresponding in crosssection to thecross-section of said yarn, a source of pressurized fluid incommunication with said chamber, and obstruction means disposed adjacentsaid opening externally of the chamber in ambient air whereby when saidyarn is threaded through said opening and pressurized fluid is providedin said chamber, the yarn is extruded from the chamber and impinges onsaid obstructing means resulting in texturing of the yarn.
 2. Apparatusfor imparting a texture to yarn as in claim 1 further including meansfor heating said textured yarn, and means for cooling said texturedyarn.
 3. Apparatus for imparting a texture to a length of yarn as inclaim 1 wherein the pressurized fluid is steam.
 4. Apparatus forimparting a texture to yarn as in claim 1 further including meteringrolls disposed in said chamber, said yarn being passed through the nipof said metering rolls prior to being threaded through said opening. 5.Apparatus for imparting a texture to yarn as in claim 1 wherein thefluid pressure within the chamber is greater than 100 p.s.i.g. 6.Apparatus for imparting a texture to yarn as in claim 1 furtherincluding a pair of metering rolls disposed in said chamber for meteringthe yarn prior to its extrusion from the chamber, and further includinga pair of crimping rolls disposed externally of the chamber, the nips ofsaid crimping rolls defining the obstruction means, and means forcoordinating the rotating of said metering rolls and said crimpingrolls.
 7. Apparatus for imparting a texture to yarn as in claim 1wherein said chamber is provided with a second opening, said secondopening substantially corresponding in cross-section to thecross-section of said yarn, which yarn is, in turn, threaded throughsaid second opening, through said pressurized chamber, and through saidfirst extrusion opening.
 8. Apparatus for imparting a texture to yarn asin claim 1 wherein said pressurized fluid is air.
 9. Apparatus forimparting a texture to yarn as in claim 1 wherein said obstruction meanscomprises of a pair of spaced, roller mounted belts, and furtherincluding heating means and cooling means disposed in the vicinity ofsaid belts in order to successively heat and cool the textured yarnpassing therethrough.
 10. Apparatus for imparting a texture to yarn asin claim 1 wherein said chamber includes two relatively moveableportions thereof defining the opening corresponding in cross-section tothe cross-section of said yarn.
 11. Apparatus for imparting a texture toyarn as in claim 1 wherein the obstruction comprises a roller drivenporous belt, the outside surface of said belt receiving the yarnextruded from said opening, while the inside surface of said belt is incommunication with a source of reduced pressure, and further includingheating means for heating said crimped yarn to permanently set same. 12.Apparatus for imparting a texture to yarn as in claim 1 wherein a highviscous fluid is provided in the region of said extrusion opening todefine an air-tight seal therewith through which said yarn is extruded.13. Apparatus for imparting a texture to yarn as in claim 1 wherein saidopening is defined by a porous metal plug fixedly secured in the wall ofsaid chamber, which plug includes an opening through which the yarn isthreaded, said plug further including a peripherial manifold which is incommunication with a source of high pressure fluid, which fluid passesthrough the porous metal plug to the vicinity of said opening in theplug for forming an air-tight seal through which the yarn is extruded.14. Apparatus for imparting a texture to yarn as in claim 1 wherein saidpressurized chamber includes a transverse opening extending transverseto the longitudinal axis of said opening, and a source of pressurizedfluid in communication with said transverse opening so as to provide acontinuous source of pressurized high viscous fluid to the opening forforming an air-tight seal through which said yarn is passed.
 15. Amethod of imparting a texture to yarn comprising the steps of: extrudingsaid yarn from a pressurized contain to ambient air through an openingtherein corresponding in cross-section to the cross-section of saidyarn; and causing said yarn to impinge on an obstructing means inambient air disposed externally of said pressuirzed chamber in thevicinity of said opening.
 16. A method for imparting a texture to alength of yarn as in claim 15 further including the steps of: heatingsaid yarn to form a permanent set in the yarn; and cooling said yarn.